Machine for applying coating material to pipe

ABSTRACT

A machine for coating pipe, making use of a dry mixture of coating materials, such as hydraulic cement, sand or gravel, and weight imparting material such as barite, iron oxide, or the like. The machine has a rotary impeller for projecting the dry mix from a supply source of the same toward the pipe to be coated, and includes moistening means, such as a water spray, through which the dry mixture passes after leaving the impeller to form a wet mixture which is impelled against the pipe. Means is provided for feeding the dry mix to the impeller in a substantially constant, regulated stream and for controlling the amount of water added whereby the consistency of the coating can be regulated. Mechanism is provided for causing the dry mix and water to be supplied simultaneously, automatically upon operation of the machine, and for independently regulating the flow of dry mix as well as the flow of water while the machine is in operation.

United States Patent [72] Inventor Robert E. Sullivan Houston, Tex.

[21] Appl. No. 810,552

[22] Filed Mar. 26, 1969 [45] Patented Apr. 20, I971 [73] AssigneeInternational Pipe Coatings, Inc.

[54] MACHINE FOR APPLYING COATING MATERIAL 422, 336, 379, 399,400,543,428; 118/303, 308, (Anti-Offset Digest 1), 300 (S) [56]References Cited UNITED STATES PATENTS 2,543,5 l 7 2/1951 Anderson239/336 3,223,329 12/1965 Ross et al 239/336 3,414,424 12/1968 Peeps etal Primary Examiner-Lloyd L. King Attorney-Charles E. Lightfoot mixtureof coating materials, such as hydraulic cement, sand or gravel, andweight imparting material such as barite, iron oxide, or the like. Themachine has a rotary impeller for projecting the dry mix from a supplysource of the same toward the pipe to be coated, and includes moisteningmeans, such as a water spray, through which the dry mixture passes afterleaving the impeller to form a wet mixture which is impelled against thepipe.

Means is provided for feeding the dry mix to the impeller in asubstantially constant, regulated stream and for controlling the amountof water added whereby the consistency of the coating can be regulated.Mechanism is provided for causing the dry mix and water to be suppliedsimultaneously, automatically upon operation of the machine, and forindependently regulating the flow of dry mix as well as the flow ofwater while the machine is in operation.

, Patented April 20, 1971 3,515,353

3 Shuts-Shoot 1 Robert E. Sullivan INVENTOR ATTORNEY Patented A ril 20,1971 3,575,353

3 Sheets-Shed 2 T FIG. 3

Robert E. Sullivan INVE N TOR ATTORNEY Patented Apfil 20, 1971 3Sheets-Sheet 3 'mm 1' M; .I

III I II II II I II II Robe/ t E. Sullivan INVENTOR MZW ATTORNEYliil/hCllllllNlE li Ollt AIPIPILIIING COATING MATERIAL TO IPIIEBACKGROUND OF THE INVENTION In the coating of pipe, and more especiallyin the application to pipe of an external protective or weight impartingcoating, such as heavy concrete, it has been customary heretofore toprepare a wet mixture of concrete which is then applied to the pipe byan impeller mechanism, such as rotary brushes, or the like. The wetconcrete mix is usually propelled horizontally onto the pipe, while thepipe is moved longitudinally and rotated, relative to the impellingmechanism, to control the thickness of the layer of concrete which isapplied. V

The coating of pipe in this manner makes it necessary to prepare largequantities of wet concrete, which is a relatively heavy material, whichmust be handled by the impeller mechanism, thus necessitating heavyimpeller equipment, expensive to maintain and operate. Moreover, thepreparation of the wet concrete mixture of the desired consistency isdifficult to accomplish, substantial variations in the consistencyresulting in laclt of proper adherence of the coating to the pipe, andthe loss of large quantities of coating material. Changes in theconsistency of the coating material are very difficult, if notimpossible, to malte during the application of the material to the pipe.

A wet mixture, for use with coating apparatus of the kind heretoforecommonly employed, is very difficult to prepare in the large quantitiesneeded and having the proper consistency to secure adequate adherence tothe pipe, while controlling the thickness of the coating which isapplied.

Attempts have been made to employ a continuous process of mixing a wetconcrete coating material for application to pipes, but due to the factthat the coating material must be prepared in very large quantities,under carefully controlled conditions, to provide a coating of constantconsistency, such methods have not proven satisfactory.

SUMMARY OF THE INVENTION briefly described, the coating apparatus of thepresent invention comprises an impeller mechanism which may be operatedto impel a dry mixed and subsequently moistened coating material againstthe external surface of a pipe which is being moved longitudinally androtated at a location to receive the coating material. The coatingmaterial is supplied to the impeller mechanism by feeding means whichreceives the dry mix from a storage hopper, and the dry mix which ispropelled toward the pipe passes through a moistening zone in whichwater is sprayed into the stream of dry mix to properly moisten the sameto accomplish the hydration of the cement and bring the mixture to aconsistency to adhere to the pipe.

The impeller mechanism is formed with a throat portion through which thedry mix moves downwardly under the influence of gravity and theadditional propulsion provided by the impeller, to form a stream ofmaterial of restricted crosssectional area which then passes through thewater spray so that the mixture is uniformly moistened during itspropulsion toward the pipe to be coated.

Memis is provided for controlling the feed of the dry mix to theimpeller mechanism, and also for controlling the amount of water whichis added to the mixture after it leaves the impeller mechanism. Means isalso provided for automatically supplying water to the dry mixture uponoperation of the impeller mechanism, and for shutting off the supply ofwater when operation of the impeller mechanism ceases.

The coating mechanism may also include means for supporting the pipe tobe coated for longitudinal movement and for rotation during suchmovement beneath the coating mechanism, whereby the thickness of thecoating applied to the pipe may be closely controlled.

BRIEF DESCRIPTION OF THE VIEWS OF THE DRAWINGS FIG. I is a sideelevational view, on a reduced scale, illustrating a preferredembodiment of the pipe coating machine of the invention, showing thesame in position for operation in the coating of a section of pipe;

FIG. 2 is an end elevational view of the invention as illustrated inFIG. 11;

FIG. 3 is a cross-sectional view, on an enlarged scale, taken along theline 3-3 of FIG. I, looking in the direction indicated by the arrows;

FIG. 4 is a cross-sectional view, taken along the line 4-4 of FIG. 3,looking in the direction indicated by the arrows; and

FIG. 5 is a diagrammatic view illustrating the piping arrangement andcontrol mechanism by which the supply of water to the machine iscontrolled and the electrical circuitry by which the operation of themachine is controlled.

DETAILED DESCRIPTION OF A PARTICULAR EMBODIMENT OF THE INVENTION Theinvention is illustrated herein in connection with its use for theapplication of a coating to the external surface of a pipe, such as thepipe P, which is suitably mounted for longitudinal movement beneath thecoating apparatus and for rotation about its axis during such movement.For this purpose, the pipe is supported for rotation on wheeledcarriages l0 and 12 which are movable along the trackway 14 extendingbeneath the coating apparatus, each of the carriages being provided witha set of spaced apart rollers, such as those shown at In and I8, uponwhich the pipe is supported at its ends, the rollers 116 of the carriageIt) being suitably driven by any usual means such as an electric motor,whereby the pipe may be rotated about its axis.

The carriage It) is also provided with suitable means for propelling thesame along the trackway M, in a usual manner. By this arrangement thepipe P may be moved longitudinally beneath the coating apparatus androtated during such movement at any desired speed while the coating isbeing applied to the exterior of the pipe.

The coating applying apparatus of the invention includes a supportingframe, generally designated 20, of generally rectangular configuration,which may be suitably mounted as by means of skids 22 which are spacedapart at suitable distance for engagement with the ground on oppositesides of the tracltway Id, to support the coating applying mechanism atany desired location along the trackway and above the same. The frame 2hmay include suitable means such as telescoping legs 2 3 by which theheight of the frame may be adjusted to maintain the coating apparatus ata desired elevation above the pipe P.

The coating mechanism includes an impeller housing, generally designated26, whose upper and lower ends are open, and which is supported at itslower end on cross members such as that shown at 28, of the supportingframe.

Within the impeller housing an' impeller, generally designated 30, isrotatably mounted on a shaft 32, mounted in suitable bearings 34 and 36,and which extends at one end beyond the impeller housing for theattachment thereto of suitable means, such as a pulley an about which adriving belt it) is extended, which may be operated by any suitablemeans such as an electric motor 42. The impeller includes a cylindricaldrum 4d suitably attached to the shaft 32 as by means of end plates asand db and to which is attached a plurality of impeller blades 50. Theblades 50 are curved and of generally rectangular shape, and each of theblades is connected to the drum by means of an arm 52 adjustablyconnected to an external ring attached to the drum as by means of a bolt5d whereby the angular position of the blade may be positioned asdesired.

The impeller housing also has a curved wall 62 along which the impellerblades pass during the rotation of the impeller to act as a fan to causea current of air to enter the lower end of the housing and to create adown draft through the throat 6t).

A downwardly extending, downwardly tapered hopper or chute 64 extendsinto the upper end of the impeller housing and is formed at its lowerend with a nozzlelike discharge outlet 66 which is vertically alignedwith the throat 60 to discharge a dry mixture of coating materialdownwardly into the throat.

Above the upper end of the trough 64 an adjustable downwardly slopingchute 68 is supported with its discharge end positioned to dischargematerial into the upper end of the hopper, and above the chute 68 adownwardly opening hopper 70 is movably supported for adjustmentlongitudinally of the chute to discharge dry mixed coating material ontothe chute.

The supply hopper 70 is adapted to be filled by a belt conveyor 72extending upwardly from the ground and which is supplied with the drymixed coating material from any desired source such as a cement mixer orthe like.

Below the discharge end of the throat 60, spaced apart parallel watersupply pipes 74 are supported, extending horizontally in the directionof the longitudinal axis of the pipe P and which pipes are perforated orprovided with suitable discharge nonles 76 spaced longitudinallytherealong and directed to discharge a spray of water which convergesdownwardly to moisten the dry mixed coating material as the same isdischarged from the throat toward the pipe P. The water supply pipes aresupplied with water from any suitable source, such as the tank 78,through a supply conduit 80, under the control of valve mechanism to bedescribed in detail hereinafter.

The control mechanism by which the operation of the apparatus iscontrolled is illustrated diagrammatically in FIG. 5 wherein the watersupply pipe 80 is shown provided with valves 82 and as, between which apressure gauge 86 is located to allow the pressure supplied through theline 80 to be adjusted as desired. The pipe 80 may also have an orificedevice 88 through which water flows through a sight gauge 90, alsoconnected into the pipe 80 and from which the water then flows to thespray pipe 74 through solenoid actuated valves 92 and 94 by which thesupply of water to the spray pipes is cut off when the impeller is notoperating.

The sight guage 9%) is of a conventional-type having a float 96 locatedtherein, past which water may flow to cause the float to rise to aheight dependent upon the amount of water which flows through the gauge.By this arrangement, the amount of water flowing through the supply pipe80 may be visually observed and the valves may be adjusted manually tomaintain the flow of water at a constant volume during the operation ofthe apparatus.

In the operation of the apparatus, constructed as described above, a drymixture of the coating materials to be applied, such as hydrauliccement, sand, or gravel, and protective or heavy materials, such asbarite, iron oxide, or the like, is prepared in any convenient manner atthe ground level and is fed into the supply hopper 70 by the elevatingconveyor 72.

The outflow of the dry mix from the supply hopper 70 to the trough 64may be conveniently controlled by adjusting the chute 68 to regulate thedownward flow of material into the trough. By this means, the dry mixmay be fed downwardly into the throat 60 through the lower end noule 66of the trough at a substantially constant rate, which may be adjusted asdesired.

As the downflow of dry mix takes place through the throat 60, theimpeller is operated at a speed to propel the mix downwardly toward thepipe P at a desired rate, the impeller blades 50 being adjustedangular'ly so that the blades clear the wall 58 of the impeller housingat a distance which will most effectively propel the mix through thethroat.

During the operation of the impeller, the impeller blades 50 act as afan to cause a current of air to be blown in the direction of the flowof the mix to cause the mix to move toward the wall 58 of the impellerhousing, thus confining the downflow of the mix and preventing thespreading or diffusion of the stream as it passes out of the lower endof the throat.

As the stream of dry mix parses downwardly from the throat 60 betweenthe water supply pipes 743, water will be sprayed from the pipe throughthe nozzle 76 into the dry mix to thoroughly moisten same, the amount ofwater so added to the dry mix being regulated by the operator to form acoating mixture which is sufficiently moistened to properly hydrate thehydraulic cement, and having a consistency to stick on the pipe P as itis impelled against the external surface of the pipe to form asubstantially uniform coating on the pipe.

In the operation of the apparatus, the operator may control the speed ofrotation of the pipe, as well as its rate of longitudinal movementbeneath the coating apparatus, and upon closing of the switch 100, themotor 42 will be operated to rotate the impeller at a predeterminedspeed while at the same time the solenoid valves 92 and 94 will beopened to supply water to the spray pipes 74. By observing the positionof the float 91 in the sight gauge 90, the operator may adjust the flowof water to the spray pipes by suitably adjusting the valves 82 and 84to maintain the float at a substantially constant position in the sightgauge, thus assuring a constant rate of supply of water to the drymixture which is being impelled toward the pipe P.

By suitably regulating the movement of the pipe beneath the coatingapparatus, as well as the rate at which the dry mixture is beingimpelled toward the pipe and the amount of water which is sprayed intothe mixture, it will be apparent that the consistency of the mixture maybe regulated as desired and the thickness of the coating which isapplied to the pipe may be controlled.

lt is to be noted that the radius of the curvature of the impellerblades 50 may be selected, and the angle of the adjustment of theseblades relative to radaii of the impeller passing through the pivotpoint provided by the bolts 54 may also be adjusted in a manner toprovide the most efficient propelling of the mixture through the throat60 while at the same time reducing any tendency to flow back in theimpeller housing, thus enabling the coating apparatus to be readilyadjusted for most efficient operation.

The coating material may be prepared as a dry mixture which is easilycontrolled, and which may be impelled against the external surface of apipe while water may be added to the dry mix during its movement towardthe pipe to control the consistency and hydration of the mixture justbefore the coating reaches the surface to which it is being applied.

Having thus clearly shown and described the invention, what is claimedas new and desired to secure by Letters Patent is:

lclaim:

1. Apparatus adapted for propelling cementitious materials onto aselected substrate and comprising: a housing having an upwardly-directedmaterial inlet and a downwardly-directed material outlet below saidinlet and aligned therewith for defining a generally-vertical paththrough said housing along which dry cementitious materials enteringsaid inlet can fall on through said housing and be discharged from saidoutlet; material-propelling means including an impeller having arotatable shaft operatively joumaled in said housing for rotation abouta generally-horizontal axis to one side of said vertical path, and aplurality of material-propelling blades circumferentially spaced aroundsaid shaft and cooperatively arranged for rotation downwardly into saidvertical path for coaction with dry cementitious materials fallingtherealong to propel such materials downwardly from said outlet toward asubstrate spatially disposed therebelow; and means spatially disposedbelow said outlet and operatively arranged for introducing water intodry cementitious materials introduced into said inlet only after suchmaterials have been propelled from said outlet by said impeller.

2. The apparatus of claim 1 further including means on said impelleradapted for selectively varying the rotational path of said blades inrelation to said vertical path of cementitious materials falling throughsaid housing.

3. The apparatus of claim 1 further including means adapted forselectively varying the angular positions of said blades on said shaftto change the rotational path of said blades in relation to saidvertical path of cementitious materials falling through said housing.

4. The apparatus of claim 1 wherein saidblades are respectively curvedforwardly in relation to the rotational direction of said impeller.

5. The apparatus of claim 4 further including means adapted forselectively varying the angular positions of said blades on said shaftto change the rotational path of said blades in relation to saidvertical path of cementitious materials falling through said housing.

6. The apparatus of claim 1 wherein said water-introducing means includespray-producing means adapted for directing a spray of water downwardlyinto cementitious materials being propelled downwardly and away fromsaid outlet.

7. The apparatus of claim 1 further including means regulating the rateat which such materials are introduced into said inlet.

2. The apparatus of claim 1 further including means on said impelleradapted for selectively varying the rotational path of said blades inrelation to said vertical path of cementitious materials falling throughsaid housing.
 3. The apparatus of claim 1 further including meansadapted for selectively varying the angular positions of said blades onsaid shaft to change the rotational path of said blades in relation tosaid vertical path of cementitious materials falling through saidhousing.
 4. The apparatus of claim 1 wherein said blades arerespectively curved forwardly in relation to the rotational direction ofsaid impeller.
 5. The apparatus of claim 4 further including meansadapted for selectively varying the angular positions of said blades onsaid shaft to change the rotational path of said blades in relation tosaid vertical path of cementitious materials falling through saidhousing.
 6. The apparatus of claim 1 wherein said water-introducingmeans include spray-producing means adapted for directing a spray ofwater downwardly into cementitious materials being propelled downwardlyand away from said outlet.
 7. The apparatus of claim 1 further includingmeans arranged above said housing and adapted for selectivelyintroducing dry cementitious materials into said inlet.
 8. The apparatusof claim 7 wherein said water-introducing means include spray-producingmeans adapted for directing a spray of water downwardly intocementitious materials being propelled downwardly and away from saidoutlet, and control means responsive to rotation of said impeller forspraying water into such cementitious materials only so long as saidimpeller is being rotated.
 9. The apparatus of claim 8 further includingmeans coupled to said material-introducing means and adapted forregulating the rate at which such materials are introduced into saidinlet.